1. Field of the Invention
The present invention relates generally to a valve, and more particularly to a ball valve.
2. Description of Related Art
As shown in FIG. 1, a prior art ball valve 40 is provided in the interior of a tubular body 41 thereof with a threaded portion 42, a rotary shaft member 1, a spherical body 2, a washer 3, and an annular locking member 43. The prior art ball valve 40 is limited in design because it can only be joined with the pipeline in a limited direction, and because it cannot be easily maintained or repaired.
As shown in FIG. 2, another prior art ball valve 50 has a tubular body 51 which is provided in the interior with a threaded port 52, a rotary shaft member 1, a spherical body 2, a washer 3, and a threaded tubular member 53. This prior art ball valve 50 cannot be easily maintained or repaired.
As shown in FIG. 3, a prior art French-type ball valve 60 has a main tubular body 61 which is provided in the interior thereof with a rotary shaft member 1, a spherical body 2, a washer 3, and a secondary tubular body 62. The prior art ball valve 60 cannot be easily maintained or replaced.
As shown in FIG. 4, a prior art ball valve 70 has a main valve body 71, which is joined with the pipeline by means of two secondary valve tubes 72. The prior art 70 is relatively complicated in construction and is therefore not cost-effective.